Figure 1.

DREPP Regulates Rhizobial Infections.

(A) Schematic representation of the DREPP gene structure and mapped Tnt1 transposon insertion sites in two independent drepp mutant alleles. UTR, untranslated region.

(B) to (F) Endogenous transcript levels were quantified by RT-qPCR (B). Values are normalized to the housekeeping gene Ubiquitin. Inset shows fold reduction of DREPP transcripts in both mutant alleles; n = 6 root systems for each genotype. Infected RHs (curled RH; see [C]) and nodules (E) were scored at 7 DAI, with n ≥ 19 root systems for each genotype and condition. (D) While several RHs developed wild-type (WT)–like ITs in drepp-1 and drepp-2 mutants, a great proportion was prematurely aborted or bacteria were released into trichoblasts (two rightmost panels). Bars = 20 µm. (F) Semithin (70-μm) longitudinal sections of 7 DAI whole nodules from the wild type and drepp mutants. Red fluorescence is derived from mCherry-labeled S. meliloti hosted in infected nodule cells. Bars = 100 µm. Data are means ± se. Statistics was performed using an unpaired two-tailed t test: *P < 0.05, ***P < 0.001.